Regulation of brakes



May 29, 1934. DEMQNGE I 1,960,481

REGULATION OF BRAKES Filed June 26, 1930 2 Sheets-Sheet 1 Z I 5 I. F 1 Ia I I i n .nn. w..."

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May 9, 34- G. DEMONGE 60,481

REGULATION OF BRAKES Filed June 25, 1930 2 Sheets-Sheet 2 2&1 2191 f i EBEES Y fiverrtor Gerard ark/70 7 6 Patented May 29, 1934 PATENT OFFICEREGULATION OF BRAKES Gerard de Monge, Liege, Belgium, assignor toFabrica Italiana Magneti Marelli, Societa Anonima, Milan, ItalyApplication June 26, 1930, Serial No. 464,065

In Belgium March 1, 1930 4 Claims.

The invention relates to mechanism for regulating the degree of vacuumexisting in a power chamber and created by the suction in the supplypipe of an internal combustion engine.

5 Such vacuum is produced in a power chamber by controlling a gaseousmedium passing through an intermediate chamber which communicates withthe power chamber; and by means of suitable connections, the effect ofthis vacuum can.

the intermediate chamber. In view of the fact that the invention obtainsmaximum braking by establishing communication between the intermediatechamber andthe intake manifold of the motor, the size of the passage forthe admission of the air to the intermediate chamber is necessarily veryslight. This small inlet has the advantage of increasing the rapidity ofestablishing the vacuum the power chamber and limiting, the air currentwhich passes through the intermediate chamber, so that the latter causespractically no changes in the condition of carburetion during thebraking.

A further object of this invention is to provide apparatus which.includes means for forming an intermediate chamber having communicationwith the atmosphere and a connection to the supply pipe of an internalcombustion engine and containing a valve and a passage cooperatingtherewith of such relative shape that the degree of vacuum in theintermediate chamber produced by the connection to the intake manifoldof the engine is approximately proportional to the extent of movement ofthe valve.

Another object of the invention is to provide mechanism for regulatingthe vacuum in a power chamber and comprising means for forming anintermediate chamber having connections as above'set forth and movablymounted in operative position.

The invention also provides that communication between the intermediatechamber and the suction manifold is established in such manner that thevacuum in the power chamber is proportional to the movement of thecontrol member of the brake.

An embodiment of the invention is illustrated by way of example on theaccompanying drawings in which:

Fig. 1 is a. diagrammatic section of the mecha" nism according to thisinvention:

. Fig. 2 is a partial section on the line II-II 0! Fig. 1,

Fig. 3 is a modification in section of a portion of the mechanism ofFig. 1,

Fig. 4 is a section of a further modification,

Fig. 5 shows diagrammatically a braking system utilizing the mechanismof Fig. 4.

In the apparatus shown on Fig. 1 the intermediate chamber 311 is adaptedto be put into communication, on the one hand, with the open air throughthe port or passage 5s or constant area and the conduit 2d; and, on theother hand, with the suction manifold 2b of an internal combustionengine through a port 28 and the conduit 20. This intermediate chamberis also in con- 76 stant communication through a conduit 4 with a powerchamber 4a. The internal combustion engine whose suction is utilized isthe motor of the vehicle to be braked by the apparatus.

The passage 5s is formed between a rod 7a and 80 an aperture in a valve5, subject to the action of a spring '5k which tends constantly to holdsaid valve on its seat 5g. Grooves, such as 5s1, are provided on theinner face of the aperture in the valve 5, to give the effect of bafliesor deflectors inthe passage 53. The eddies created in the passage 5s bythese grooves have an action equivalent'to that of a reduction in thecross section of said passage. Arranged on the control rodQ'la is a.closure member 6, adapted to move opposite the port 2s and to more orless uncover the latter so as to regulate the area of the communicationbetween the intermediate chamber 3d and the conduit 20.

The rod 7a is moved for actuation of the brakes by operating the brakepedal (not shown) of the vehicle and is done in opposition to the actionof a spring 5m. The spring 5m abuts against the outside of theatmospheric conduit 2d at one end and against the collar 5a on the rod7a at the other. Thus the spring is compressed whenever the rod 7a movesthe reciprocable valve 6 to open the port or passage 2s.

Two collars 7b and 7b1 are also arranged on the rod 7a. The distancewhich separates these collars-is equal to the movement of rod 7a duringoperation of the brake, that is to say, from minimum braking(application oi the brake bands to the brake drums) up to thepractically maximum braking. The result of this arrange- 10 ment is thaton maximum braking the collar lb closes the passage 5s because it hasthen moved up close to the end of this passage; and the port 2s is nowfully uncovered by the valve 6; and that on rapid release the collar 7hrremoves the valve 5 from its seat so as to produce free communicationbetween the intermediate chamber 3d and the conduit 2d leading to theatmosphere. This result follows because the rod 7a now moves in theother direction bringing the collar 'Ibi against the other side of thevalve 5.

In practice (see Fig. 1) the outside air enters into the intermediatechamber through the passage 5s and discharges into the suction manifold2b of the motor through the port 2s whose efiec tive area is determinedby the position of the closure member 6 and the rod 7a. The size of port2s and passage 53 determines the extent of the vacuum in theintermediate chamber and hence in the brake power 4a.

The profile or outline of the above mentioned port 28 (see Fig. 2) issuch that the vacuum in the intermediate chamber is proportional to themovement of the valve 6.

In case the rod 7a. is connected to the brake pedal through a floatinglever, which is joined directly to the vehicle brakes, it is to be notedtransmitting to the brakes the effort exerted by I the driver on thebrake pedal. If, for example,

the total course or movement of the valve 6 is 10 mm., the first two ofwhich permit the flow of ,air in the intermediate chamber between the'conduits 2d and 2c and the last millimeter 01 Y which serves to actuatethe collar 72), there remain '1 mm. for progressive operation of thebrakes. I

In Fig. 3, the device which controls the communication between theintermediate chamber 3d and the conduit 2d terminating in the open airis formed by a cylindrical member 5b aflixed to the drive rod 7a andprovided with a circular .flange' 5d and a valve 7d. The circularshutter is formed so as to move in the intermediate chamber 3d duringthe entire period of braking so as to leave a passage of constant area58 between the conduit 2d and said intermediate chamber. The valve la isintended to close said communication when it engages a seat 8 duringcomplete braking. The distance separating the valve 7d from the seat 8is equal to the length of movementof the rod 7a during the entire periodof braking, so that on complete release (produced by moving rod 7a inthe direction of the arrow X) the flange Sdpasses out of theintermediate chamber andthus allows free entrance of air.

into the latter., The vacuum in the intermediate chamber is regulated ina manner similar to that of the case of Fig. l, by actuation of theclosure member 6.

The device shown in Figs. 1, 2 and 3 can advantageously be made out oftubing oi! the proper size joined together; or in any other-manner.

through the passage 41'.

'or plunger 7e which has a close sliding fit with brake rods which areactuated when the bellows contracts. 7

In the construction shown in Figs. 3 and 4 the constant opening of smallcross-section of the communication with the atmosphere is obtained bymeans of-a circular shutter 5d 0r 5dr sliding in a conduit 3d or 3dr ofslightly greater diameter, so as to leave for the air fiow a reducedpassage of constant cross-section independent of the movements of theshutter as well as of that 0 all the valves.

In the case of Fig. 5, the controller (an enlarged sectional view ofwhich is shown on Fig. 4) has the form of a hollow casing 8a interposeddirectly between the brake pedal 15 and the lever 11 of the brake gearthrough the rods 9a and 9b. This lever 11 is connected rigidly to an arm11b, connected by cables 110 and 11d to the brake organs proper. Thebrakes are shown as mounted upon arms or levers 12c and 12d connected tothe cables or links 110 or 11d respectively; and while the arm 11b andlever 11 are rigid with respect to each other, there is a common pivotat their point of connection about which these parts turn in unison.Lever 11 is also subject to 1 'the action of a retractile spring llawhich tends to move it in a direction opposite that of the arrow Ytoward the brake release position.

The intermediate chamber 3(11 in the casing 8a communicates with thepower chamber 4m It may also be put in communication with the atmospherethrough the conduit 2th, and with the motor intake through the conduit21);. A passage is formed by the annular space left between the flange5dr and 1 the inner surface of the intermediate chamber. Control ofcommunication between said intermediate chamber and conduit 2hr iseffected by means of a valve 61 having an approximately parabolic l'orm.This parabolic form is selected so 1 that the degree of vacuum in theintermediate chamber is approximately proportional to the movement ofthis valve.

To effect braking action, pressure is exerted on pedal lever 1550 as totransmit force to lever 11 through the spring 5mi' in the end of thecasing 8a; the compression of this spring thus causes relative movementbetween the valve 61 and the casing 8a so as to produce communicationbetween the intermediate chamber and passage 2b1. The degree of vacuumin this chamber increases with the effort exerted on the brake pedal.

The effect of the vacuum produced in the in.- termediate chamber istransmitted to-the power chamber 4m. The movable bar 4a: of the latteracts to move lever 11 in the direction of the arrow Y. I

During complete braking the valve 7b: is pressed to its seat 81 andserves to directly transmit the force exerted on the pedal to the lever11.

On rapid release rod 701 moves to the position shown on Fig. 4. The rod7a; is rigid with respect to the valve 61, and this rod bears a collarthe inside of the chamber 3dr; and forms a movable partition between oneend of this chamber and a recess in the end of the casing 8a receivingthe spring 51m. This recess has a closure 5m with an opening for the rodIa and the collar 7e prevents leakage between the recess for the spring51m and the chamber 3dr. Under the action of the air admitted into thepower chamber 4m the lever 11 moves in the brake release direction,

which produces a movement or the rod 92) connecting lever 11 to rod 7m,to compress spring 51221. It is to be noted that when the controller isinoperative, it rests against a stop 10a in such a manner as to leave aslight communication between the intermediate chamber and the intakemanifold of the engine as by causing the flange 7b: to engage its seatloosely at this time and to keep the flange 5111 in said intermediatechamber, so that there exists in thelatter and in the brake cylinder aslight vacuum to maintain the diiferent elements of the brake gear undertension.

The casing So can be made in any suitable manner to provide the chamber3d1 and the passages which enable this chamber to communicate with theconduits 2b1, 2d and 41; and may comprise several pieces or sections asshown in Fig. 4 suitably united together; or in one piece, if preferred;with couplings and openings to connect .the conduits with the chamber3d1.

What I claim is: 1. Controlling apparatus including means for forming apower motor, means for forming an intermediate chamber connected to thepower motor, the intermediate chamber having a conduit for putting thesame in communication with the intake manifold of an internal combustionengine, and a second conduit open tothe atmosphere, a slidable rod insaid intermediate chamber, said rod having at one end a tapering valveto control communication through the intermediate chamber between thepower motor and the first-named conduit, said rod carrying a secondvalve having a flange to restrict communication between the intermediatechamber and the atmosphere and to cut off said communication, saidvalves and the interior of said intermediate chamber having such shapethat the inflow 01' air to said intermediate chamber from the atmosphereis substantially constant when the valves are moved to open thefirstnamed conduit and the amount of air withdrawn from said chamberthru the first-named conduit is proportional to the degree of movementof said valves.

2. Controlling apparatus including means for forming a power motor,movably mounted means for forming an intermediatechamber connected tothe power motor, the intermediate chamber having a conduit for puttingthe same in communication with the i takemanifold of an internalcombustion engine, and a second conduit open to the atmosphere, theintermediate chamber also being connected to the power motor, a slidablerod in said intermediate chamber, said rod having at one end a taperingvalve to control communication through the intermediate chamber betweenthe power motor and the firstnamed conduit, said rod carrying a secondvalve having a flange to restrict communication between the intermediatechamber and the atmosphere and to cut off said communication, saidvalves and the interior of the intermediate chamber being of such shapethat the inflow of air to the intermediate chamber is substantiallyconbrake member to be actuated and connections.

from said member to the power motor to enable the latter to operate saidmember when the intermediate chamber is in communication with saidmanifold.

3. Regulating mechanism comprising means for forming a power motor,movably mounted means for forming an intermediate chamber connected tothe power chamber, the intermediate chamber having a conduit for puttingthe same in communication with the intake manifold of an internalcombustion engine, and a second conduit open to the atmosphere, aslidable rod in said intermediate chamber, said rod having at one end atapering valve fixed thereon to control communication through theintermediate chamber between the power motor and the firstnamed conduitsaid rod carrying a second valve fixed thereon having a flange torestrict communication between the intermediate chamber and theatmosphere and to cut off said communication, one end of saidintermediate chamber being shaped to be connected with an actu- 4.Controlling apparatus including means for forming a power motor, meansfor forming an intermediate chamber connected to the motor, said chamberhaving a conduit for establishing communication with the intake manifoldof an internal combustion engine, and a second conduit open to theatmosphere, a reciprocable rod in said chamber, the rod having a valvefixed thereon at one end to control communication through the chamberbetween the motor and the first-named conduit, said rod also having asecond valve flxed thereon including a flange or collar to controlcommunication between the intermediate chamber and the atmosphere and tocut on said communication, the intermediate chamber having passages ofsuch shape relative to the valves that the inflow of air to said chamberfrom said atmosphere is substantially constant when the valves are'movedto open the first-named conduit, and the amount GERARD m: MONGE.

